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Full text of "Alaskan glacier studies of the National Geographic Society in the Yakutat Bay, Prince William Sound and lower Copper River regions"

GLACIERS OF AIASKA                                       15
Some of the glaciers of the interior of Kenai Peninsulax were observed by Mendenhall in 1898 and Moffit in 1904.1 In 1908 and 1909 Grant mapped the fronts of many of the glaciers of eastern and southern Kenai Peninsula.2 The former were studied in 1910 by the junior author of this book, and are described in later chapters.
THE ALASKA RANGE
Olaciers of the Nutzotin and Mentasta Mountains. The eastern end of the Alaska Range includes the Nutzotin and Mentasta Mountains which rise to heights of 5000 to 10,000 feet. Being relatively low and in a region of low precipitation, because in the lee of the higher Chugach and Wrangell Mountains of the St. Elias Range, they nourish only a few small glaciers, some of which were seen by Brooks in 1899,8 by Schrader and Witherspoon in 1902 4 and by Moffit, Knopf, and Capps in 1908.6
Glaciers of the Copper River Headwaters. The region between Mt. KLmball and Mt. Hayes in the Alaska Range rises to heights of from 8000 to 13,000 feet. It must receive more snowfall than the same range farther to the east, in the lee of Wrangell Mountains, for it has large snowfields and sends good-sized glaciers southward into the Copper River valley and smaller ones northward into the drainage basin of the Tanana and Yukon. These ice tongues include the Chistochina, West Fork, Gakona, Gulkana, Canwell, and Casjner Glaciers. The first three glaciers drain to Copper River and the Pacific Ocean, the last two to the Tanana and Yukon Rivers and Bering Sea, while Gulkana Glacier sends one stream each way.
Gakona Glacier is a simple, single, consequent, valley glacier 13 miles long and 3 miles wide and with its direction of flow at right angles to the axis of the Alaska Range. West Fork Glacier is similarly simple. East of Mt. Kimball is a series of three small consequent valley glaciers, each about five miles long, which enter an east-west valley parallel to the axis of the range. The easternmost of the three glaciers turns eastward in an un-symmetrical piedmont bulb a mile long, draining to Slana River. The -westernmost similarly turns westward in a one-sided piedmont bulb a mile long, draining to the Middle Fork of Chistochina River. The middle glacier makes a symmetrical bulb whose drainage also goes westward under the last-named glacier. These are consequent valley glaciers terminated by piedmont bulbs which divide a subsequent valley into two compartments.
West of these little glaciers is Chistochina Glacier, a piedmont through glacier in a later stage of development. It heads in two valleys, Middle and West Forks of Chistochina River. It is 10 miles long, a mile and a half to two miles wide and extends east and west paralleling the axis of the Alaska Range, from which it is fed by seven consequent valley glaciers two to four miles long, and by four smaller tributaries from the lower hills on the south. This seems to be a subsequent glacier.
i Mendenhall, W. C, 20th Ann. Rept., U. S. Geol. Survey, Part VH, 1900, pp. 328-329.
Moffit, F. H., Bull 277, U. S. Geol. Survey, 1906, pp. 31-32 and map, PI. H
1 Grant, IT. S. and Higgins, D. F., Coastal Glaciers of Prince William Sound and Kenai Peninsula, Bull. 526, U. S. Geol. Survey, 1913, pp. 52^72, see Bull, 879, U. S. Geol. Survey, 1909, PI. IV; Journ, Geol., Vol. XVII, 1909, pp. 670-671, and Bull. Amer. Geog. Soc., Vol. XLIH, 1911, pp. 721-787.
• Brooks, A. H., 21st Ann. Rept., U. S. Geol. Survey, Part n, 1901, p. 364. «Professional Paper 41, U. S. Geol. Survey, 1905, PI. XX.
• Moffit, F. H. and Knopf, A., Bull. 379, U. S, Geol. Survey, 1909, pp. 162, 169. Capps, S. R., Journ. Geol., Vol. XVUI, 1910, p. 36.